Stability of inverse olefin emulsions: influence of the incorporation of fine solids of different chemical natures

Abstract

The chemical nature of solids incorporated into the drilling fluid can be very diverse, since it is related to the type of rock formation. As a result, it can lead to different impacts on the properties of the emulsions, which are the bases for drilling fluids formulation. In view of this, this work aimed to evaluate the influence of the chemical nature of finely divided solids on physical properties and interfacial phenomena of inverse olefin emulsions. For this purpose, emulsions were prepared using linear olefin and NaCl brine, as continuous and dispersed phases, respectively. Each emulsion was incorporated with limestone and clay, in the proportion of 5% v/v. The emulsions were characterized by means of optical microscopy, rheological behavior and gravitational separation tests. The results showed that chemical nature and particle size of bentonite clay ensures a more efficient interfacial interaction with emulsion droplets. The emulsion added with bentonite clay showed a significant increase in consistency index and smaller separated volume. Thus, the addition of bentonite clay to olefin emulsions resulted in changes on its properties, which contributes to emulsion stability.